C-reactive protein (CRP) is the prototypical acute phase protein; serum levels of CRP may increase as much as 2000-fold during the early stages of the inflammatory response. Although CRP was discovered in 1930, the function of this protein is not known. This project is directed toward an understanding of the function of CRP in order to learn how the body responds to inflammatory stimuli. A. Peptide synthesis - The primary structure of human CRP reveals three peptide sequences that may cause immunomodulation. Three peptides corresponding to three sequences were synthesized and studied for immunomodulating activity. B. Immunomodulating assays - Assays to measure monocyte chemotaxis, superoxide production and IL-1 production were employed to test the activity of the CRP peptides. The significance of the programs lies in the identification of new mediators of inflammation.